This invention is directed toward rapidly dispersible absorbent products and methods for making and using such products. This invention is especially directed toward rapidly dispersible absorbent products that are flushable down a standard toilet system.
Disposable absorbent articles such as feminine hygiene products, diapers, training pants, adult incontinence products, offer great convenience and are widely used by consumers. However, the popularity of these products has created a need regarding their disposal. Typical disposal methods such as incineration or landfill are generally considered unsatisfactory because of cost and environmental concerns. An alternative disposal method has been in practice, which involves flushing the article down the conventional toilet, subsequently, degrading it in the municipal or private sewage system or septic system. This disposal method is generally considered convenient and discrete. For this disposal method, the suitable materials should not only maintain its structural integrity for the intended use but also disintegrate readily such that the material can be flushed down the conventional toilet and plumbing system without creating blockage. These materials requirements become more challenging in the pre-moistened applications where the materials need to have storage stability for a long period of time in a wet condition. Additionally, the suitable materials are preferably biodegradable such that there is no accumulation of large chunks of the materials in the waste handling system.
Numerous approaches have been tried to provide flushable fibrous products for use in a variety of uses including, but not necessarily limited to, sanitary napkins, diapers, toilet seat wipes, and the like. For example: U.S. Pat. No. 5,300,358 issued Apr. 5, 1994 to Evers discloses a degradable and flushable absorbent structure for sanitary napkins, diapers, and the like having an absorbent fibrous core and a backsheet comprising a cold water soluble material; U.S. Pat. No. 4,575,891 issued Mar. 18, 1986 to M. Valente discloses a small flushable toilet seat wipe of approximately 2 inches by 2 inches having a cardboard upper layer; GB Patent Publication 2,281,081, published Feb. 22, 1995 by R. L. Lewis et al. discloses a web of fibrous material and polymeric binder which is said to be sufficiently hydro-disintegratable to be flushed down a toilet. The binder is applied by spraying or dipping onto wet-laid or air-laid webs. EP patent Publication 896,089 A1 published Feb. 10, 1999 by Taakeuchi et al. discloses a fibrous sheet that is disintegratable when immersed in large amounts of water comprising a fibrous sheet treated with a binder such as polyvinyl alcohol. U.S. Pat. No. 4,734,941 issued Apr. 5, 1988 to De Witt et al. discloses a flushable urine-conducting product for positioning between the legs of a female to direct urine to a receptacle. The product comprises a fibrous or non-fibrous sheet that is disintegratable in water and a water soluble polymer film. The preferred disintegratable sheet is tissue paper. U.S. Pat. No. 5,509,913 issued Apr. 23, 1996 to Yeo discloses a toilet flushable product such as diapers, fabrics, and sheets for use as wipes that are insoluble in the presence of body waste fluid but soluble in the presence of normal tap water.
There is a need for a convenient, easy-to-use, and easy to dispose of absorbent product which effectively cleans or absorbs residual body exudates, and then can be readily disposed of in any toilet and subsequent waste handling system (e.g., sewer, septic tank). Therefore, it is desirable to provide absorbent products useful for absorption of residual body exudates that are sufficiently dispersible such that they can be easily flushed down toilets and passes readily through plumbing.
It is further desirable to provide degradable products such that they do not accumulate substantially in the sewer, septic tank, or other waste handling systems.
It is also desirable to provide pre-moistened products that are stable in storage, dispersible in the toilet/disposal system, and degradable in the sewer, septic, or other waste handling system.
It is also desirable to provide for a mechanically weakened web such that it breaks up and is dispersible during disposal yet retains sufficient integrity that it does not break up during use.
It is further desirable to provide products pre-moistened with a liquid or a composition such that they deliver hard surface cleaning, skin cleaning, skin conditioning and/or other skin benefits.
These and other needs addresses by the invention as hereinafter described may become apparent to one of ordinary skill in the art are intended to be encompassed by the present invention in accordance with the claims which follow.
The present invention provides dispersible absorbent products comprising a mechanically weakened fibrous web. The dispersible absorbent products can absorb a sufficient amount of fluid without becoming overloaded and suffering from leakage, and can be easily disposed using a standard toilet. The mechanically weakened regions of the web enhance the dispersibility of the product. Additionally, the dispersible absorbent products may be pre-moistened with a composition suitable for delivering hard surface cleaning or polishing, household cleaning or polishing, skin cleansing, skin conditioning, and like cleaning, conditioning, polishing benefits. The pre-moistened products are stable in storage and dispersible in a standard toilet. This invention further provides methods of making such dispersible absorbent products by mechanically weakening a fibrous web.